I have searched and searched but could not find anything on the actual removing of the vfad.

I just took mine out and realized it is extremely easy to do.

So here is my step by step on taking it off.

Remove front bumper.
Take bolt of fabric tube its 10mm
pop off the foam piece by the to pop of clips
take of plastic cover in front of vfad by 3 pop off retainers
take the last 2 retainers of vfad and pull straight out
pull off hose from valve.
your done.

I went a step farther and took out all the tubing from the engine to the vfad to make it a clean removal now there is a sensor that goes to the vfad that has a harness plugged into it. So i just caped both tubes on it and left it on but everything else has been plugged and fully removed.

So should i remove that sensor as well.

My car runs good i have a bit of backfire but i think that is just because the ecu is still adjusting to the change in intake.

could you possibly post some pictures of your vfad removal? they would really help the explaination... either way what were the effects? better or worse mileage? pickup? sound? idleing? etc...?

could you possibly post some pictures of your vfad removal? they would really help the explaination... either way what were the effects? better or worse mileage? pickup? sound? idleing? etc...?


Sound is a lot more aggressive definetely louder. It has a bit more pickup mainly under heavy acceleration because you dont have that slight hesistation when the vfad opens and closes.

I will have better results here in a few days once my ecu gets adjusted to the new setup. I did reset it but it needs to gather all its info now.

i dont really have any pics i just took it out was fast and was not thinking about posting it on but i could get some pics of the parts i took out.

in an otherwise OEM setup, your likely loosing out on TOTAL performance by doing this.... that design was chosen to keep the intake as efficient as possible at all RPMs. doing this you may find minor gains in a certain area(low/high rpm) but for total power/torque under the curve, i'd bet money your loosing out....

i dont understand the stuff well enough to explain it, but i've read many of RotaryGod's and other posts on intake runner length and the whole idea of tuning the intake.... they all lead to the same conclusion, for a NON-BOOSTED application, Mazda pretty much hit the nail right on the head. some gains can be found, but you'll pay for them in other areas.

yeah id love to see all you took out if you get the chance

you may be right about that but i am not staying oem for long i am getting a lot of aftermarket upgrades here in a few weeks

Cobb ecu tune
custom exhaust
turbo
coilovers
new rims
full body kit
carbon fiber spoiler

so i figured having all of that on the way i could justify taking all that off the intake.

and the vfad is mostly for noise reduction not really for performance so the loose or gain we are talking about here is ~1hp at most i did it mainly for the sound that is it i had no thought of performance doing this most mods to the intake are purely for noise nothing else you cant get much of a gain off the stock intake but you can take all the noise reduction off.

I just looked it up and on the manual 8 the VFADs second duct doesnt open until 5500rpm so id guess taking it off would give you 30-50% more air into the engine... never hurts right?

did this today along with a throttle body bypass. very cool

could set lean codes.

kevin.

IMy car runs good i have a bit of backfire but i think that is just because the ecu is still adjusting to the change in intake.

:uhh:

i have been driving my car ALL DAY... the throttle body bypass + removed vfad + k&n filter + removed panels in airbox + drilled holes in front bumper grill = very VERY AWESOME!! oh god, it's so nice of a sound, not to loud. at some rpms it produces a nice deep growl. and it cost me 10$ to do it all! (well a friend bought me the filter)

i couldnt find any pics of what it looks like removed so i took one with mine out, here it what it looks like -

Thanks dale, not knowing the repercussions of the tubing and sensor disconnection I was afraid to do this.

Ive got the K&N typhoon2, the one that looks like a funnel, and a large vent in my front bumper right in front of the vfad module, both are in direct line with eachother (someone planned ahead)

I see people writing not good to do this. I think Im gonna take the dive tomorrow afternoon and see if my car is still running or not.

in case your wondering what im talking about here is a pic of the bumper, I am hoping it functions like a ram air hood. I know the WS6 firebird had a ram air that added a good amount of power past 50-60mph (the pignose hood). and behind that my airbox is completely closed off from the rest of the engine bay.

http://i75.photobucket.com/albums/i312/david_worden/1shrunk.jpg

i have an intake and an exhaust. Will this mod do anything for me? what does VFAD stand for>?

could set lean codes.

kevin.

how so? RB duct deletes vfad, but I've never heard anyone running lean because of it

I never removed my VFAD. Just zipptied it up lol

VFAD = Variable Fresh Air Duct

used for low/ middle rpm noise cancelling vs high rpm straight through air flow (with no concern over noise levels)

no lean codes, no ecu codes what so ever.
gained about 1 maybe 2 miles to the gallon on the highway (i commute alot) but i think this has to do with the open duct in my front bumper some.
the sound is not that much louder, although i have a typhoon 2 intake so it was loud to begin with.
but i did notice that long idle times are not as bad on initial take off, you know how if you sit at a stop light for a while and go to start again, it feels sluggish. I have a short ram so while sitting still it sucks in hot engine bay air. after doing this, all my issues with hot air intake while idleing is pretty much gone.

I can tell physically as well, go for a long drive before without redlining, just normal driving and touch the intake box after. its going to be REALLY warm. take off the vfad, go for a long drive, my filter was actually cool.

i really do think it had something to do with the hole in the bumper though. but there are DIYs on here on how to put one in and have it look good for cheap.

once again, thanks man for the write up that convinced me to jump. gained a couple ponies and some MPG from this....not much, but every bit helps and adds up in the end.

is there a way to rig the vfad so that it is constantly open? if it was constantly open, would there be a great need for RBs ram air?

i couldnt find any pics of what it looks like removed so i took one with mine out, here it what it looks like -

You're suppose to remove that plastic piece too.

http://img25.imageshack.us/img25/627/gfdgdfg.jpg (http://img25.imageshack.us/my.php?image=gfdgdfg.jpg)
http://img25.imageshack.us/img25/gfdgdfg.jpg/1/w512.png (http://g.imageshack.us/img25/gfdgdfg.jpg/1/)

is there a way to rig the vfad so that it is constantly open? Yes, buy an intake that deletes it. Or buy an Accessport. if it was constantly open, would there be a great need for RBs ram air? I didn't know that there WAS a great need for RBs ram air.

is there a way to rig the vfad so that it is constantly open? if it was constantly open, would there be a great need for RBs ram air?

Dude take the tubing out. Remove it and get the RB ram duct.

is there a way to rig the vfad so that it is constantly open? if it was constantly open, would there be a great need for RBs ram air?

If you have a constant vacuum then you can... but there are two intake ports on the VFAD (One will close up and the other will open) so you're still not getting as much air in unless you completely remove the VFAD.

well i did it!!!! i think??.. i spent my day figuring this thing out.. i have a K&N intake and figured that the VFAD looked pointless since i got a short ram intake.. i took the VFAD out and left the little valve vacum line thing that opens and shuts the VFAD door, uncapped... is that alright?? for all i know its still sucking in air... i couldnt find any kind of sensor that DALE said he wanted to remove.. oh weLL.. i guess im about a 1LB lighter now.... LOL.. it was a fun DIY! i also did the cooler oil DIY vents... thanx DIY!!

well i did it!!!! i think??.. i spent my day figuring this thing out.. i have a K&N intake and figured that the VFAD looked pointless since i got a short ram intake.. i took the VFAD out and left the little valve vacum line thing that opens and shuts the VFAD door, uncapped... is that alright?? for all i know its still sucking in air... i couldnt find any kind of sensor that DALE said he wanted to remove.. oh weLL.. i guess im about a 1LB lighter now.... LOL.. it was a fun DIY! i also did the cooler oil DIY vents... thanx DIY!!

cap it

Take a pick of how you blocked everything off. I want to see what you did :)

You really just need to cap the nipple behind the throttle body.
This is the "beginning" of the vacuum line for the VFAD.
136611

Autozone sells a pack of vacuum caps of various sizes.

There's a reason that a Mazdaspeed/aftermarket cold air intake is louder.

"All air all the time." ;)

As shown elsewhere, cap the vacuum line that stock-controls the VFAD 'shutter' when removing it, otherwise the air pump will be overworked.

As shown elsewhere, cap the vacuum line that stock-controls the VFAD 'shutter' when removing it, otherwise the air pump will be overworked.
:uhh: What air pump are you referring to?
Once you cap the nipple behind the throttle body (as I showed two post above), there are no other vacuum lines that need capped nor is there a pump anywhere in the VFAD system.

If the stock "air duct" was kept on the car, you can keep the VFAD valve open at all times by simply disconnecting the vacuum line from the VFAD actuator since it needs 10psi of vacuum to close it fully (which is why it has a vacuum chamber and a one-way valve inline).

aka Vacuum pump.

I was talking about the nipple behind the throttle body. For some reason I didn't see your post/picture Jon.

:uhh: What air pump are you referring to?
Once you cap the nipple behind the throttle body (as I showed two post above), there are no other vacuum lines that need capped nor is there a pump anywhere in the VFAD system.

If the stock "air duct" was kept on the car, you can keep the VFAD valve open at all times by simply disconnecting the vacuum line from the VFAD actuator since it needs 10psi of vacuum to close it fully (which is why it has a vacuum chamber and a one-way valve inline).

aka Vacuum pump.
I won't get technically picky.... we're on the same page ;)

I was talking about the nipple behind the throttle body. For some reason I didn't see your post/picture Jon.
Its OK... I'm sure others just skip over my posts too :lol2:

The Mazda shop manual refers to it as an 'air pump.' I don't like that either, but I was trying to be technically picky. ;)

You always have good posts and I really didn't see it. Strange 'net glitch today (Full Moon)?

I won't get technically picky.... we're on the same page ;)


Its OK... I'm sure others just skip over my posts too :lol2:

The Mazda shop manual refers to it as an 'air pump.'

Really?
136627

Its all in good (and knowledgeable) fun Huey52.
Think you and I have "thumped our chest" enough yet? :lol2:

O'rly? A vacuum chamber but an air pump. ;) (I'm not really a last word must have guy, but this is fun)

Really?
136627

Its all in good (and knowledgeable) fun Huey52.
Think you and I have "thumped our chest" enough yet? :lol2:

so i capped it from the intake manifold jus like in the picture.. thanx jon.. but in the process of removing the hose i snapped off the lil buger i was suppose to cap off.. *&(^%*$%%:banghead:, weLL i took a glue stick (its the thing that needs a hot glue gun to melt it) and sealed off the hole.. hopefully that holds in place.. about the green harness,somewere around the check valve, connected to the sensor, well can that be unplugged so i can remove the whole Vacum assembly?

about the green harness,somewere around the check valve, connected to the sensor, well can that be unplugged so i can remove the whole Vacum assembly?

That green harness is for the VFAD solenoid.
You can disconnect it and zip-tie it out of the way.
Then remove the solenoid and the rest of the hoses.

I'm going to Autozone to cap that sucker! what wires can I remove that are connected to the the Vfad? I has one that cliped to some hose. I'll see if I can take and post pix of it. I just want to clean up my engine bay :)

Everything that is inline between the nipple behind the throttle body and the VFAD valve can be removed (reference layout above in post #34).
Obviously, the solenoid harness will need to be zip-tied out of the way.

Whats the the solenoid harness? lol I'm a no0b :lol:

Whats the the solenoid harness?

I've since concealed my harness inside wire loom and wrapped it with electrical tape, but I managed to find the only photo I took that had it showing.
136755
Its the electrical connection to the VFAD solenoid valve.
You can see the VFAD vacuum chamber laying just below it on the under tray.
Later on I removed the whole under tray because it was ugly.

Oh I get it. Yeah thats how mine looks right now. Hey can I remove the parts that I followed in red in the attachment I posted?
Thanks!

Hey can I remove the parts that I followed in red in the attachment I posted?

Yup!

Sooo I went to do this last night, got everything apart only to find out that the owner before me had already removed it...atleast I know how to take the bumper off now lol

Took my VFAD off today and I can notice that is almost double or triple the loudness. I can also feel a little more in the butt dyno

Took my VFAD off today and I can notice that is almost double or triple the loudness. I can also feel a little more in the butt dyno

yeah, its freakin sweet

Took my VFAD off today and I can notice that is almost double or triple the loudness. I can also feel a little more in the butt dyno

Ok I don't get this...I took my car apart and there is no vfad to be found, but my car is not loud at all! Is there anyway that it is possibly intact somewhere and is not actually removed?

Ok I don't get this...I took my car apart and there is no vfad to be found, but my car is not loud at all! Is there anyway that it is possibly intact somewhere and is not actually removed?

no
loud is relative i guess. go drive a car with vfad still on and you will see the difference, especially on full throttle under 5k-ish

hell, stock intake w/o vfad is louder than some aftermarket intakes (revi for one)

Took mine out the other day but ran out of time to take out all the wires up to the uim. I capped the hose where it rests behind the filter box; is that good enough?

Took mine out the other day but ran out of time to take out all the wires up to the uim. I capped the hose where it rests behind the filter box; is that good enough?

You can technically cap it anywhere before the VFAD actuator.
As long as you don't introduce a vacuum leak into your intake, you're OK.
That means you can cap the solenoid, the vacuum chamber, the one-way valve, etc.
BUT... if you plan on removing the hoses running up to the VFAD (which would look a lot better) then you need to cap the nipple behind the throttle body and simply remove the rest.

Now it also won't hurt anything to keep some of the piping in place (like under the air box).
So if for some reason you only want to remove the assembly up to the solenoid (from the intake manifold) and not bother going any "deeper" into it, that is fine too.
You won't even need to cap anything because the VFAD valve needs vacuum to close and simply leaving the piping "uncapped" won't harm anything.
Again, the only thing that NEEDS capped is the nipple behind the throttle body.

Yes, that's good enough. I purposely capped there to make return to stock easier if desired.

..... I capped the hose where it rests behind the filter box; is that good enough?

yeah same here

ok i am slightly confused. I have studied jons diagrams and seen the video and have a question. Does simply caping off the nipple behind the throttle body keep the vfad open since it needs vaccum to close it? :Wconfused

ok i am slightly confused. I have studied jons diagrams and seen the video and have a question. Does simply caping off the nipple behind the throttle body keep the vfad open since it needs vaccum to close it? :Wconfused

You are correct.
As long as you don't introduce vacuum back into the line, the valve will stay open.

Now... if you only remove the hose behind the throttle body, the valve will stay closed because the VFAD solenoid is closed and keeping vacuum in the line to the actuator.
Two easy ways around this.
1) When you drive your car and take the RPM above 5500, the solenoid will open and release the remaining vacuum in the line.
2)Remove the line connected to the solenoid (line going to the actuator) and you'll hear the vacuum escape. Then just reinsert the hose onto the solenoid so its not dangling.

i have a stock 04 6MT...i have a k&n drop-in filter. should i even bother with this mod?

Its totally up to you.
Nice thing is, if you cap the nipple behind the throttle body to keep the VFAD open at all times and you find out a few days later that you don't like it, just remove the cap and reinstall the hose.
Very easy to go back as long as you don't remove anything like the solenoid, vacuum chamber, and the one-way valve.
Then if you do like the "mod" and want to remove the components (to make it look cleaner), you can do that.

ok, i went out to do this and my throttle body does not seem to have the nipple or hose running down as shown in you're pics/diagrams. Very strange, as theres just nothing there on that side. I will try to post pics tom of my throttle body. I have a 05 if that helps at all.

^Do you have a 4-port engine?

i beleive so but im not sure. how do i tell? srry i just got my 8 not to long ago and i am still learning alot. but im pretty sure it's not 6 port. thanks for the help!

The 4-ports didn't have a VFAD installed... so if you don't have that nipple behind the throttle body, more than likely its a 4-port.

They have the FAD (Fresh Air Duct) but not the VFAD (Variable Fresh Air Duct).

They have the FAD (Fresh Air Duct) but not the VFAD (Variable Fresh Air Duct).

Correct.
This was posted earlier in this thread:
141734
The FAD is the tube running off to the left and the VFAD is the piece facing forward with the actuator attached to the right side.
The 4-ports don't have the VFAD part installed.

gotcha. however, when i hit 4,300 rpm (automatic) it definitely gets alot louder and revs quicker. is this some variation of vfad or is that just the nature the 4 port renesis. i have always been told thats the vfad opening

edit: ok so i have a fad, not vfad. does this mean since its not "variable" it's always open?

If you have an '05 auto, you don't have a VFAD.
The VFAD normally opens at 5500rpm (if you have it), the SSV (secondary shutter valve) opens at 3250rpm which is on all models.

edit: ok so i have a fad, not vfad. does this mean since its not "variable" it's always open?

You don't have that whole VFAD piece/body there.
Its just the FAD tube straight into the engine bay.

If you have an '05 auto, you don't have a VFAD.
The VFAD normally opens at 5500rpm (if you have it), the SSV (secondary shutter valve) opens at 3250rpm which is on all models.

ok. thanks alot for the help

No problem.
I did a quick and dirty Photoshop job on the pic above to show the FAD (without the VFAD).
141735

Its not exact but close enough.
I couldn't find a real pic quick enough :)

or you can buy a HKS CF duct thats mounts in front you just drill a hole rx ocho has it on his i'm looking to doing mine too

or you can buy a HKS CF duct thats mounts in front you just drill a hole

Or buy a RB duct and you don't have to drill a thing ;)

^ah true true

Well today I removed the hose going to the intake and capped it with a rubber grommet (looks like a plastic valve cap) I don't notice any difference in sound but I notice that there is no hesitation around the 5500 RPM mark. Some have said that it should be louder. Just curious if others are noticing the same thing.

It's only a little louder, but the biggest benefit is the lack of hesitation where the VFAD would have normally transitioned.

Ban the VFAD. ;)

keep in mind you have butterfly valves in the intake manifold that open around 5k as well. thats where the stumble is. but when you get rid of the vfad it might help a little to provide less vaccum resistence so it gives the perception of more responce to the motor due to less piping. its like a short ram, works better for top end, cold air long tube works for the bottom end of the range more.

and as for the rb duct, you have 2 full 90 degree bends before it goes into the intake pipe. but if you use a straight forward duct it will help alot more. exspecially on the k/n intake with a surround to provide positive pressure.

The in-motion "ram air effect" of the RB duct easily overcomes the slight resistance of the two bends. But intakes are more about suction than intake pressure anyway, in that the engine will take all it can get. Yes I know we talk about FI in terms of "boost" (increased air pressure to achieve denser oxygen rich air) but our, and most other, engines run starved for air as stock.

Also keep in mind the 2nd set of injectors that come into play around 5k rpm. Removing the VFAD won't of course have any bearing on those, but again removing it does eliminate the VFAD shutter transition lag.

You really just need to cap the nipple behind the throttle body.
This is the "beginning" of the vacuum line for the VFAD.
136611

Autozone sells a pack of vacuum caps of various sizes.

Could i do this with stock intake flaps removed??? or do i have to have an after market intake? and what exactly do i disconnect? if i cap the lil thingy what else is there to do. i need some specifics :)

Any infromation on removing what looks like a chamber on the left (driver) side of the intake. (Its a 4"x4"x2" estimate looking plastic chamber connecting to the intake between the MAF and the TB. Looks like a brake fluid cap sized hole if i removed it) I capped the VFAD line right in front of this "chamber", before the check valve and TB. Plan on removing the whole system this saturday and just was wondering what removing this "chamber" would do?? My VFAD lines dont run like in the previous schematic post but functionally I believe its the same.

EDIT: air pulse damper is what i think that chamber im talking about is called. From a fluid dynamics point of view I can;t see why they would put a empty chamber on the side of the intake?????

^If its the chamber on the flexible intake tube, that's a resonance chamber.
Removing that will only make your car louder.

<---- rotary noobie
What is advantage of capping off VFAD?

By not introducing vacuum back into the VFAD line, the valve stays open at all times.
It is really used to reduce engine noise below 5500rpm.
At 5500rpm the valve opens to allow a 2nd air inlet into the intake.
Some people claim to feel a difference, but I believe that the increase sound makes it appear that the car is moving faster.

lol yep... actually the other day I utilized the removed vfad area to construct a cold air duct into the stock airbox from the front bumper grill

I capped my VFAD after work yesterday and i can tell a little different in loudness and just a hint of better throttle response. It's a nice little tweak i guess to put on the roster yaaa meannn

I'll cap it after work today. What do I do with the hanging hose? just tie wrap it?

I'll cap it after work today. What do I do with the hanging hose? just tie wrap it?

With the vacuum line disconnected from the nipple, if you don't zip-tie it out of the way the hose can get caught in the belt or pulley.

Finally did this today...no lag as it opens anymore. Seems like better throttle response, and a little faster rev. I dont think it got any louder, but the tone definatly changed for the better.

I joined the club, my car "feels" faster. :)

i think it made a little difference with throttle response but damn its louder

Jon
Will not having the solenoid conected thow a code? Thats the main reason i kept mine.

Jon
Will not having the solenoid conected thow a code? Thats the main reason i kept mine.

No.
The VFAD valve doesn't have a position switch like the SSV and VDI.
Same reason why people who have aftermarket intakes like the AEM and MS don't receive a CEL since they completely remove the whole VFAD assembly.

Jon, I removed the valve behind the tb and caped it. what do I do with all the other wires and what do I do with the plastic electircal thing? just disconnect it and remove all that?

Jon, I removed the valve behind the tb and caped it.
There is no valve behind the throttle body.
But as long as you capped the nipple behind the TB, you're all good.

what do I do with all the other wires and what do I do with the plastic electircal thing? just disconnect it and remove all that?
The hoses can be removed along with the vacuum chamber and solenoid if you want.
Zip-tie the wire harness for the solenoid somewhere off to the side.

Or you can just remove the hoses between the vacuum chamber and the upper intake manifold (has a own-way valve on it).

did you get my pm?

did you get my pm?

Yes... just responded.

No.
The VFAD valve doesn't have a position switch like the SSV and VDI.
Same reason why people who have aftermarket intakes like the AEM and MS don't receive a CEL since they completely remove the whole VFAD assembly.

Thanks, ripped the hole thing out with confidence now. I also connected the solenoid wires to an empty terminal or prong (what ever you would call that) that sits right above where the solenoid was.

Thought I'd chime in. This wasn't as easy a DIY as I thought it would be, but then again I'm fairly new to working on my car. Anyways, I believe I did everything right, but I didn't give maximum effort like some of you seem to have. Is the plugging of the hole by the throttle body for those who took out all the wiring/hoses and stuff? I simply disconnected as close to the Vfad thing, leaving me with a rubber hose that I plugged.

Anyways, I only took a short drive with the vfad removed so far, and it's alright. About a week ago I took out the baffles inside the air intake box and noticed that off the line it seemed I could get going quicker without bogging down. This seems to have reversed that. But on the upside, it does make the engine a bit louder. I took it on the freeway and floored it in sixth, and was surprised to hear a deeper, louder growl from the Renesis. It was still painfully slow, but atleast it sounded like I was going fast. Those with an exhaust, intake, or other powertrain mods probably wouldn't notice much of a difference, but for someone like me who is otherwise stock, I'd recommend it.

It's fine to leave the vacuum hosing and yes plugging it at the throttle body is only if you removed it all. Actually, leaving the lines makes it easier to return to stock. You don't have to plug the line at the former VFAD actuator locale, but I did to keep the line clean.

I wouldn't modify the stock airbox. Rather get a K&N flat filter element.

The major benefit to removing the VFAD is that it eliminates the hesitiation that was felt when the damper was transitioning to full airflow. With it removed it's only a little bit louder and only below 4500 rpm (low end noise abatement is why the VFAD was designed in the first place).

Thought I'd chime in. This wasn't as easy a DIY as I thought it would be, but then again I'm fairly new to working on my car. Anyways, I believe I did everything right, but I didn't give maximum effort like some of you seem to have. Is the plugging of the hole by the throttle body for those who took out all the wiring/hoses and stuff? I simply disconnected as close to the Vfad thing, leaving me with a rubber hose that I plugged.

Anyways, I only took a short drive with the vfad removed so far, and it's alright. About a week ago I took out the baffles inside the air intake box and noticed that off the line it seemed I could get going quicker without bogging down. This seems to have reversed that. But on the upside, it does make the engine a bit louder. I took it on the freeway and floored it in sixth, and was surprised to hear a deeper, louder growl from the Renesis. It was still painfully slow, but atleast it sounded like I was going fast. Those with an exhaust, intake, or other powertrain mods probably wouldn't notice much of a difference, but for someone like me who is otherwise stock, I'd recommend it.

i de-walled the airbox, dropped in a K&N highflow filter, and removed the VFAD this weekend. It was a breeze. I think actually the first time I worked on my car and nothing went wrong! Im sure i jinxed myself....

where can i buy the cap to cap the throttle bypass nipple?

where can i buy the cap to cap the throttle bypass nipple?

Autozone sells a variety pack of vacuum caps for a couple dollars.

Autozone sells a variety pack of vacuum caps for a couple dollars.
did you get a certain size or verity pack

did you get a certain size or verity pack

I just got the variety pack because I didn't know the size of the nipple, plus it was only a couple dollars so no big deal.
I don't recall which size I ended up using.

thanks for the update:smoker:

Plus the variety pack has the cap you need for your oil overflow nipple when you install a catch can. ;)

I just got the variety pack because I didn't know the size of the nipple, plus it was only a couple dollars so no big deal.
I don't recall which size I ended up using.

Plus the variety pack has the cap you need for your oil overflow nipple when you install a catch can. ;)

Touché :yesnod:

Well that was a nice and easy mod thanks for the help. I just had never seen a need to pay all that money when we already have a short shot intake that comes stock with a little modification

^ Yep, now just mate a Racing Beat Ram Duct to the stock box, drop in a K&N flat filter, and you're there. ;)

See Brettus DIY

Sorry to barge in but I recently reinstalled my V-Fad and wanted to illustrate (show off) how I did it and why.

http://www.rx8club.com/showthread.php?t=192959

if the 04 AT GT doesnt have the VFAD but does have the FAD, can I remove the FAD?

if the 04 AT GT doesnt have the VFAD but does have the FAD, can I remove the FAD?

You can... question is why would you want to (or feel the need to)?
Only reasoning I can think of is if you wanted to replace it with Racing Beat's air duct.

ok i got a k&n typhoon v2 from my uncle as a gift
i heard it sucks in the engine bay air
if i cap the "nipple" will this help me gain power
i just wanna cap the "nipple" behind the TB with no other work. Will this help

Ok I am a little confused....

I have a 2006 6sp MT. Does mine have the VFad system? or is it Fad?

I understand there is no benefit to removing the Fad system. only the Vfad...

You have a VFAD.

Ok I am a little confused....

I have a 2006 6sp MT. Does mine have the VFad system? or is it Fad?

I understand there is no benefit to removing the Fad system. only the Vfad...

After removing the vfad today, (stock air box and drop in k&n) i got a CEL about 20 miles later. I can't remember the exact code but it was something like intake manifold tuning valve stuck open bank 1. i reset the code for now. I also capped off the vac line for the VAFD. Any ideas?

this mod looks tempting until I remembered that every car I've owned I've switched to an aftermarket intake--only to return to stock soon after.

removed mine this weekend and haven't seen any downsides, the only difference is that now, every time I open the throttle up and my revs are below 5k there is a very nice and deep growl that comes from the intake, its quite enjoyable. As for performance I can feel the engine is a bit more lively, specially upper in the rpm band but no solid data. Hopefully I'll be adding the revi ram ir duct soon.

So does a 04 manual gt have vfad? I currently and running into boost issues being my boost is at a very good constant till about 3000rpm and then the boost drops off and my power is drastically dropped, I've been trying to dyno it, but I keep only making 220 whp. I currently have the BNR Greddy turbo upgraded kit, any help would be awesome thanks. It kinda sounds like to me this could be the problem?

If you have a turbo you shouldn't have the air box correct? If there is no air box your vfad will not be connected to anything. And I'm assuming that you have a front mount intercooler and if that was installed most likely the vfad should have been removed.

I couldn't find a vacuum cap in my neighborhood pep boys.. will these from amazon do the job?
http://www.amazon.com/Spectre-4254-Vacuum-Cap-Set/dp/B000BPWSCC

I couldn't find a vacuum cap in my neighborhood pep boys
I know Autozone sells a variety pack with the correct size... just get it there.

If not those are the exact ones autozone sells, they were 6.99 or 7.99 at autozone I think.

noobish question. but if i remove my VFAD will it trigger a cel?

noobish question. but if i remove my VFAD will it trigger a cel?
No, the VFAD is only connected to the engine with a vacuum hose. Be sure to plug the hose once it is removed.

I decided to go back to using the VFAD. I never actually disconnected it completely, I just removed one hose so it was always stuck open like this or another thread suggested. Recently I was getting some idle issues where my idle would dive down to 600-700 rpm and then jump up to 1200-1500 quickly. I thought maybe its time to change my coils out(was at almost 36k miles) I did that and idle issue went away for about a week but then came back the exact same.

Then I thought the only thing left to check is the VFAD since that is the only thing modified in the engine bay. I removed my vacuum cap on the TB and re attached the VFAD hose and now its been weeks and no idle issues at all. Maybe it was because I did not fully remove the VFAD, I don't know. I don't know enough about the VFAD or why mazda put it there to start second guessing them, and it was obviously causing me trouble with it set to always open so its back to stock forever for that part.

i thought you could just get rid of VFAD with Cobb, right?

do we leave the styro foam and the nose support off or put it back on? thanks.

do we leave the styro foam and the nose support off or put it back on? thanks.

Take the time to read the whole thread.
Then you'll see that its not worth it to remove the duct and the VFAD can simply be bypassed if that is what you desire.
And when I say bypass... I'm simply saying you can prevent the valve from closing to keep it open at all times.
Keep in mind, the valve is closed at lower RPMs simply to keep the engine noise down.
Bypassing the valve will only increase the sound coming from the intake... nothing more.

please read the thread in it's entirety before posting questions, thank you

.

Take the time to read the whole thread.
Then you'll see that its not worth it to remove the duct and the VFAD can simply be bypassed if that is what you desire.
And when I say bypass... I'm simply saying you can prevent the valve from closing to keep it open at all times.
Keep in mind, the valve is closed at lower RPMs simply to keep the engine noise down.
Bypassing the valve will only increase the sound coming from the intake... nothing more.

i already took the vfad off... and loving it. I was just wondering if i should put the foam and nose support back in. is there any good reason to have these back on? will my bumper sag if i leave the nose support off? thanks